Malignant melanoma remains the most deadly skin cancer with no effective drugs available for the long-term treatment of patients. The melanoma community believes that therapies targeting key proteins or pathways promoting metastatic melanoma development is needed that act in a synergistic manner to effectively treat this disease. While it's thought that the MAP and PI3 kinase pathways need to be inhibited along with other key pathways, the identity of particular genes to target and therapeutics to accomplish this objective do not currently exist for melanoma. Targeting key kinases deregulated in disseminated melanoma using siRNA-based agents is one approach but the identity of kinases to target using siRNA for synergistically acting tumor inhibition remains unknown and delivery of siRNA in animals remains a challenge. Our long-term goal is to develop therapeutic agents inhibiting proteins deregulated in metastatic melanoma to shrink tumors in a synergistically acting manner. To accomplish this objective, the central hypothesis proposes that siRNA-targeting Akt3, V600EB-Raf and other key kinases deregulated in melanoma can be loaded into nanoliposomes and used to synergistically inhibit metastatic disease development. The central hypothesis will be evaluated by: (1) Identifying which key kinases when targeted along with V600EB-Raf and Akt3 lead to synergistically acting tumor inhibition. An siRNA-based screen will be used to identify kinases deregulated in melanoma cell lines, validate involvement in tumor as well as metastasis development and determine whether inhibition along with V600EB-Raf and Akt3 leads to synergistic inhibition. (2) Evaluating whether nanoliposomes containing siRNA-targeting V600EB-Raf, Akt3 and other key kinases deregulated in melanoma can inhibit metastatic disease in a synergistically acting manner. Nanoliposomes containing siRNA designed to target V600EB-Raf, Akt3 and other key kinases in melanoma will be developed and efficacy for synergistically inhibiting metastatic melanoma development evaluated in animals. Development of synergistically acting therapeutic agents targeting key kinases promoting melanoma metastasis development would be a significant, novel and innovative scientific advancement. These agents would lay the foundation for a new category of therapeutic drug to more effectively treat patients suffering from disseminated melanoma. Long- term it would increase the currently available small arsenal of effective therapeutics for treating metastatic disease, thereby directly decreasing mortality rates. PUBLIC HEALTH RELEVANCE: Development of synergistically acting therapeutic agents to inhibit disseminated metastatic melanoma would be a significant, novel and innovative scientific advancement. Studies outlined in this proposal would demonstrate the feasibility of therapeutic nanoliposomes containing siRNA-targeting Akt3, V600EB-Raf and other key kinases deregulated in melanoma to inhibit tumor development in a synergistically acting manner. Furthermore, they would lay the foundation for a new category of therapeutic drugs to more effectively treat patients suffering from this disease. Long-term it would increase the currently available small arsenal of effective therapeutics for treating disseminated metastatic melanoma, thereby directly decreasing mortality rates.